NTP authoritative US Government site

I currently point an AIX server to us.pool.ntp.org sources for time. I am being required to use an authoritative US Government site. Is anyone doing this? If yes can you supply me with the a link or list of time servers. I am in the Central time zone. Thanks in advance.

Where you are located have nothing with the case. Better escalate problem to your managers, they should escalate it further till someone know or have access to appropriate documents. On this question only authorized personnel from US Government can provide you answer